fs/btrfs/delayed-inode.c

   1 /*
   2  * Copyright (C) 2011 Fujitsu.  All rights reserved.
   3  * Written by Miao Xie <miaox@cn.fujitsu.com>
   4  *
   5  * This program is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU General Public
   7  * License v2 as published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public
  15  * License along with this program; if not, write to the
  16  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  17  * Boston, MA 021110-1307, USA.
  18  */
  19
  20 #include <linux/slab.h>
  21 #include "delayed-inode.h"
  22 #include "disk-io.h"
  23 #include "transaction.h"
  24 #include "ctree.h"
  25
  26 #define BTRFS_DELAYED_WRITEBACK         512
  27 #define BTRFS_DELAYED_BACKGROUND        128
  28 #define BTRFS_DELAYED_BATCH             16
  29
  30 static struct kmem_cache *delayed_node_cache;
  31
  32 int __init btrfs_delayed_inode_init(void)
  33 {
  34         delayed_node_cache = kmem_cache_create("btrfs_delayed_node",
  35                                         sizeof(struct btrfs_delayed_node),
  36                                         0,
  37                                         SLAB_MEM_SPREAD,
  38                                         NULL);
  39         if (!delayed_node_cache)
  40                 return -ENOMEM;
  41         return 0;
  42 }
  43
  44 void btrfs_delayed_inode_exit(void)
  45 {
  46         kmem_cache_destroy(delayed_node_cache);
  47 }
  48
  49 static inline void btrfs_init_delayed_node(
  50                                 struct btrfs_delayed_node *delayed_node,
  51                                 struct btrfs_root *root, u64 inode_id)
  52 {
  53         delayed_node->root = root;
  54         delayed_node->inode_id = inode_id;
  55         atomic_set(&delayed_node->refs, 0);
  56         delayed_node->ins_root = RB_ROOT;
  57         delayed_node->del_root = RB_ROOT;
  58         mutex_init(&delayed_node->mutex);
  59         INIT_LIST_HEAD(&delayed_node->n_list);
  60         INIT_LIST_HEAD(&delayed_node->p_list);
  61 }
  62
  63 static inline int btrfs_is_continuous_delayed_item(
  64                                         struct btrfs_delayed_item *item1,
  65                                         struct btrfs_delayed_item *item2)
  66 {
  67         if (item1->key.type == BTRFS_DIR_INDEX_KEY &&
  68             item1->key.objectid == item2->key.objectid &&
  69             item1->key.type == item2->key.type &&
  70             item1->key.offset + 1 == item2->key.offset)
  71                 return 1;
  72         return 0;
  73 }
  74
  75 static struct btrfs_delayed_node *btrfs_get_delayed_node(struct btrfs_inode *btrfs_inode)
  76 {
  77         struct btrfs_root *root = btrfs_inode->root;
  78         u64 ino = btrfs_ino(btrfs_inode);
  79         struct btrfs_delayed_node *node;
  80
  81         node = READ_ONCE(btrfs_inode->delayed_node);
  82         if (node) {
  83                 atomic_inc(&node->refs);
  84                 return node;
  85         }
  86
  87         spin_lock(&root->inode_lock);
  88         node = radix_tree_lookup(&root->delayed_nodes_tree, ino);
  89         if (node) {
  90                 if (btrfs_inode->delayed_node) {
  91                         atomic_inc(&node->refs);        /* can be accessed */
  92                         BUG_ON(btrfs_inode->delayed_node != node);
  93                         spin_unlock(&root->inode_lock);
  94                         return node;
  95                 }
  96                 btrfs_inode->delayed_node = node;
  97                 /* can be accessed and cached in the inode */
  98                 atomic_add(2, &node->refs);
  99                 spin_unlock(&root->inode_lock);
 100                 return node;
 101         }
 102         spin_unlock(&root->inode_lock);
 103
 104         return NULL;
 105 }
 106
 107 /* Will return either the node or PTR_ERR(-ENOMEM) */
 108 static struct btrfs_delayed_node *btrfs_get_or_create_delayed_node(
 109                                                         struct btrfs_inode *btrfs_inode)
 110 {
 111         struct btrfs_delayed_node *node;
 112         struct btrfs_root *root = btrfs_inode->root;
 113         u64 ino = btrfs_ino(btrfs_inode);
 114         int ret;
 115
 116 again:
 117         node = btrfs_get_delayed_node(btrfs_inode);
 118         if (node)
 119                 return node;
 120
 121         node = kmem_cache_zalloc(delayed_node_cache, GFP_NOFS);
 122         if (!node)
 123                 return ERR_PTR(-ENOMEM);
 124         btrfs_init_delayed_node(node, root, ino);
 125
 126         /* cached in the btrfs inode and can be accessed */
 127         atomic_add(2, &node->refs);
 128
 129         ret = radix_tree_preload(GFP_NOFS);
 130         if (ret) {
 131                 kmem_cache_free(delayed_node_cache, node);
 132                 return ERR_PTR(ret);
 133         }
 134
 135         spin_lock(&root->inode_lock);
 136         ret = radix_tree_insert(&root->delayed_nodes_tree, ino, node);
 137         if (ret == -EEXIST) {
 138                 spin_unlock(&root->inode_lock);
 139                 kmem_cache_free(delayed_node_cache, node);
 140                 radix_tree_preload_end();
 141                 goto again;
 142         }
 143         btrfs_inode->delayed_node = node;
 144         spin_unlock(&root->inode_lock);
 145         radix_tree_preload_end();
 146
 147         return node;
 148 }
 149
 150 /*
 151  * Call it when holding delayed_node->mutex
 152  *
 153  * If mod = 1, add this node into the prepared list.
 154  */
 155 static void btrfs_queue_delayed_node(struct btrfs_delayed_root *root,
 156                                      struct btrfs_delayed_node *node,
 157                                      int mod)
 158 {
 159         spin_lock(&root->lock);
 160         if (test_bit(BTRFS_DELAYED_NODE_IN_LIST, &node->flags)) {
 161                 if (!list_empty(&node->p_list))
 162                         list_move_tail(&node->p_list, &root->prepare_list);
 163                 else if (mod)
 164                         list_add_tail(&node->p_list, &root->prepare_list);
 165         } else {
 166                 list_add_tail(&node->n_list, &root->node_list);
 167                 list_add_tail(&node->p_list, &root->prepare_list);
 168                 atomic_inc(&node->refs);        /* inserted into list */
 169                 root->nodes++;
 170                 set_bit(BTRFS_DELAYED_NODE_IN_LIST, &node->flags);
 171         }
 172         spin_unlock(&root->lock);
 173 }
 174
 175 /* Call it when holding delayed_node->mutex */
 176 static void btrfs_dequeue_delayed_node(struct btrfs_delayed_root *root,
 177                                        struct btrfs_delayed_node *node)
 178 {
 179         spin_lock(&root->lock);
 180         if (test_bit(BTRFS_DELAYED_NODE_IN_LIST, &node->flags)) {
 181                 root->nodes--;
 182                 atomic_dec(&node->refs);        /* not in the list */
 183                 list_del_init(&node->n_list);
 184                 if (!list_empty(&node->p_list))
 185                         list_del_init(&node->p_list);
 186                 clear_bit(BTRFS_DELAYED_NODE_IN_LIST, &node->flags);
 187         }
 188         spin_unlock(&root->lock);
 189 }
 190
 191 static struct btrfs_delayed_node *btrfs_first_delayed_node(
 192                         struct btrfs_delayed_root *delayed_root)
 193 {
 194         struct list_head *p;
 195         struct btrfs_delayed_node *node = NULL;
 196
 197         spin_lock(&delayed_root->lock);
 198         if (list_empty(&delayed_root->node_list))
 199                 goto out;
 200
 201         p = delayed_root->node_list.next;
 202         node = list_entry(p, struct btrfs_delayed_node, n_list);
 203         atomic_inc(&node->refs);
 204 out:
 205         spin_unlock(&delayed_root->lock);
 206
 207         return node;
 208 }
 209
 210 static struct btrfs_delayed_node *btrfs_next_delayed_node(
 211                                                 struct btrfs_delayed_node *node)
 212 {
 213         struct btrfs_delayed_root *delayed_root;
 214         struct list_head *p;
 215         struct btrfs_delayed_node *next = NULL;
 216
 217         delayed_root = node->root->fs_info->delayed_root;
 218         spin_lock(&delayed_root->lock);
 219         if (!test_bit(BTRFS_DELAYED_NODE_IN_LIST, &node->flags)) {
 220                 /* not in the list */
 221                 if (list_empty(&delayed_root->node_list))
 222                         goto out;
 223                 p = delayed_root->node_list.next;
 224         } else if (list_is_last(&node->n_list, &delayed_root->node_list))
 225                 goto out;
 226         else
 227                 p = node->n_list.next;
 228
 229         next = list_entry(p, struct btrfs_delayed_node, n_list);
 230         atomic_inc(&next->refs);
 231 out:
 232         spin_unlock(&delayed_root->lock);
 233
 234         return next;
 235 }
 236
 237 static void __btrfs_release_delayed_node(
 238                                 struct btrfs_delayed_node *delayed_node,
 239                                 int mod)
 240 {
 241         struct btrfs_delayed_root *delayed_root;
 242
 243         if (!delayed_node)
 244                 return;
 245
 246         delayed_root = delayed_node->root->fs_info->delayed_root;
 247
 248         mutex_lock(&delayed_node->mutex);
 249         if (delayed_node->count)
 250                 btrfs_queue_delayed_node(delayed_root, delayed_node, mod);
 251         else
 252                 btrfs_dequeue_delayed_node(delayed_root, delayed_node);
 253         mutex_unlock(&delayed_node->mutex);
 254
 255         if (atomic_dec_and_test(&delayed_node->refs)) {
 256                 bool free = false;
 257                 struct btrfs_root *root = delayed_node->root;
 258                 spin_lock(&root->inode_lock);
 259                 if (atomic_read(&delayed_node->refs) == 0) {
 260                         radix_tree_delete(&root->delayed_nodes_tree,
 261                                           delayed_node->inode_id);
 262                         free = true;
 263                 }
 264                 spin_unlock(&root->inode_lock);
 265                 if (free)
 266                         kmem_cache_free(delayed_node_cache, delayed_node);
 267         }
 268 }
 269
 270 static inline void btrfs_release_delayed_node(struct btrfs_delayed_node *node)
 271 {
 272         __btrfs_release_delayed_node(node, 0);
 273 }
 274
 275 static struct btrfs_delayed_node *btrfs_first_prepared_delayed_node(
 276                                         struct btrfs_delayed_root *delayed_root)
 277 {
 278         struct list_head *p;
 279         struct btrfs_delayed_node *node = NULL;
 280
 281         spin_lock(&delayed_root->lock);
 282         if (list_empty(&delayed_root->prepare_list))
 283                 goto out;
 284
 285         p = delayed_root->prepare_list.next;
 286         list_del_init(p);
 287         node = list_entry(p, struct btrfs_delayed_node, p_list);
 288         atomic_inc(&node->refs);
 289 out:
 290         spin_unlock(&delayed_root->lock);
 291
 292         return node;
 293 }
 294
 295 static inline void btrfs_release_prepared_delayed_node(
 296                                         struct btrfs_delayed_node *node)
 297 {
 298         __btrfs_release_delayed_node(node, 1);
 299 }
 300
 301 static struct btrfs_delayed_item *btrfs_alloc_delayed_item(u32 data_len)
 302 {
 303         struct btrfs_delayed_item *item;
 304         item = kmalloc(sizeof(*item) + data_len, GFP_NOFS);
 305         if (item) {
 306                 item->data_len = data_len;
 307                 item->ins_or_del = 0;
 308                 item->bytes_reserved = 0;
 309                 item->delayed_node = NULL;
 310                 atomic_set(&item->refs, 1);
 311         }
 312         return item;
 313 }
 314
 315 /*
 316  * __btrfs_lookup_delayed_item - look up the delayed item by key
 317  * @delayed_node: pointer to the delayed node
 318  * @key:          the key to look up
 319  * @prev:         used to store the prev item if the right item isn't found
 320  * @next:         used to store the next item if the right item isn't found
 321  *
 322  * Note: if we don't find the right item, we will return the prev item and
 323  * the next item.
 324  */
 325 static struct btrfs_delayed_item *__btrfs_lookup_delayed_item(
 326                                 struct rb_root *root,
 327                                 struct btrfs_key *key,
 328                                 struct btrfs_delayed_item **prev,
 329                                 struct btrfs_delayed_item **next)
 330 {
 331         struct rb_node *node, *prev_node = NULL;
 332         struct btrfs_delayed_item *delayed_item = NULL;
 333         int ret = 0;
 334
 335         node = root->rb_node;
 336
 337         while (node) {
 338                 delayed_item = rb_entry(node, struct btrfs_delayed_item,
 339                                         rb_node);
 340                 prev_node = node;
 341                 ret = btrfs_comp_cpu_keys(&delayed_item->key, key);
 342                 if (ret < 0)
 343                         node = node->rb_right;
 344                 else if (ret > 0)
 345                         node = node->rb_left;
 346                 else
 347                         return delayed_item;
 348         }
 349
 350         if (prev) {
 351                 if (!prev_node)
 352                         *prev = NULL;
 353                 else if (ret < 0)
 354                         *prev = delayed_item;
 355                 else if ((node = rb_prev(prev_node)) != NULL) {
 356                         *prev = rb_entry(node, struct btrfs_delayed_item,
 357                                          rb_node);
 358                 } else
 359                         *prev = NULL;
 360         }
 361
 362         if (next) {
 363                 if (!prev_node)
 364                         *next = NULL;
 365                 else if (ret > 0)
 366                         *next = delayed_item;
 367                 else if ((node = rb_next(prev_node)) != NULL) {
 368                         *next = rb_entry(node, struct btrfs_delayed_item,
 369                                          rb_node);
 370                 } else
 371                         *next = NULL;
 372         }
 373         return NULL;
 374 }
 375
 376 static struct btrfs_delayed_item *__btrfs_lookup_delayed_insertion_item(
 377                                         struct btrfs_delayed_node *delayed_node,
 378                                         struct btrfs_key *key)
 379 {
 380         return __btrfs_lookup_delayed_item(&delayed_node->ins_root, key,
 381                                            NULL, NULL);
 382 }
 383
 384 static int __btrfs_add_delayed_item(struct btrfs_delayed_node *delayed_node,
 385                                     struct btrfs_delayed_item *ins,
 386                                     int action)
 387 {
 388         struct rb_node **p, *node;
 389         struct rb_node *parent_node = NULL;
 390         struct rb_root *root;
 391         struct btrfs_delayed_item *item;
 392         int cmp;
 393
 394         if (action == BTRFS_DELAYED_INSERTION_ITEM)
 395                 root = &delayed_node->ins_root;
 396         else if (action == BTRFS_DELAYED_DELETION_ITEM)
 397                 root = &delayed_node->del_root;
 398         else
 399                 BUG();
 400         p = &root->rb_node;
 401         node = &ins->rb_node;
 402
 403         while (*p) {
 404                 parent_node = *p;
 405                 item = rb_entry(parent_node, struct btrfs_delayed_item,
 406                                  rb_node);
 407
 408                 cmp = btrfs_comp_cpu_keys(&item->key, &ins->key);
 409                 if (cmp < 0)
 410                         p = &(*p)->rb_right;
 411                 else if (cmp > 0)
 412                         p = &(*p)->rb_left;
 413                 else
 414                         return -EEXIST;
 415         }
 416
 417         rb_link_node(node, parent_node, p);
 418         rb_insert_color(node, root);
 419         ins->delayed_node = delayed_node;
 420         ins->ins_or_del = action;
 421
 422         if (ins->key.type == BTRFS_DIR_INDEX_KEY &&
 423             action == BTRFS_DELAYED_INSERTION_ITEM &&
 424             ins->key.offset >= delayed_node->index_cnt)
 425                         delayed_node->index_cnt = ins->key.offset + 1;
 426
 427         delayed_node->count++;
 428         atomic_inc(&delayed_node->root->fs_info->delayed_root->items);
 429         return 0;
 430 }
 431
 432 static int __btrfs_add_delayed_insertion_item(struct btrfs_delayed_node *node,
 433                                               struct btrfs_delayed_item *item)
 434 {
 435         return __btrfs_add_delayed_item(node, item,
 436                                         BTRFS_DELAYED_INSERTION_ITEM);
 437 }
 438
 439 static int __btrfs_add_delayed_deletion_item(struct btrfs_delayed_node *node,
 440                                              struct btrfs_delayed_item *item)
 441 {
 442         return __btrfs_add_delayed_item(node, item,
 443                                         BTRFS_DELAYED_DELETION_ITEM);
 444 }
 445
 446 static void finish_one_item(struct btrfs_delayed_root *delayed_root)
 447 {
 448         int seq = atomic_inc_return(&delayed_root->items_seq);
 449
 450         /*
 451          * atomic_dec_return implies a barrier for waitqueue_active
 452          */
 453         if ((atomic_dec_return(&delayed_root->items) <
 454             BTRFS_DELAYED_BACKGROUND || seq % BTRFS_DELAYED_BATCH == 0) &&
 455             waitqueue_active(&delayed_root->wait))
 456                 wake_up(&delayed_root->wait);
 457 }
 458
 459 static void __btrfs_remove_delayed_item(struct btrfs_delayed_item *delayed_item)
 460 {
 461         struct rb_root *root;
 462         struct btrfs_delayed_root *delayed_root;
 463
 464         delayed_root = delayed_item->delayed_node->root->fs_info->delayed_root;
 465
 466         BUG_ON(!delayed_root);
 467         BUG_ON(delayed_item->ins_or_del != BTRFS_DELAYED_DELETION_ITEM &&
 468                delayed_item->ins_or_del != BTRFS_DELAYED_INSERTION_ITEM);
 469
 470         if (delayed_item->ins_or_del == BTRFS_DELAYED_INSERTION_ITEM)
 471                 root = &delayed_item->delayed_node->ins_root;
 472         else
 473                 root = &delayed_item->delayed_node->del_root;
 474
 475         rb_erase(&delayed_item->rb_node, root);
 476         delayed_item->delayed_node->count--;
 477
 478         finish_one_item(delayed_root);
 479 }
 480
 481 static void btrfs_release_delayed_item(struct btrfs_delayed_item *item)
 482 {
 483         if (item) {
 484                 __btrfs_remove_delayed_item(item);
 485                 if (atomic_dec_and_test(&item->refs))
 486                         kfree(item);
 487         }
 488 }
 489
 490 static struct btrfs_delayed_item *__btrfs_first_delayed_insertion_item(
 491                                         struct btrfs_delayed_node *delayed_node)
 492 {
 493         struct rb_node *p;
 494         struct btrfs_delayed_item *item = NULL;
 495
 496         p = rb_first(&delayed_node->ins_root);
 497         if (p)
 498                 item = rb_entry(p, struct btrfs_delayed_item, rb_node);
 499
 500         return item;
 501 }
 502
 503 static struct btrfs_delayed_item *__btrfs_first_delayed_deletion_item(
 504                                         struct btrfs_delayed_node *delayed_node)
 505 {
 506         struct rb_node *p;
 507         struct btrfs_delayed_item *item = NULL;
 508
 509         p = rb_first(&delayed_node->del_root);
 510         if (p)
 511                 item = rb_entry(p, struct btrfs_delayed_item, rb_node);
 512
 513         return item;
 514 }
 515
 516 static struct btrfs_delayed_item *__btrfs_next_delayed_item(
 517                                                 struct btrfs_delayed_item *item)
 518 {
 519         struct rb_node *p;
 520         struct btrfs_delayed_item *next = NULL;
 521
 522         p = rb_next(&item->rb_node);
 523         if (p)
 524                 next = rb_entry(p, struct btrfs_delayed_item, rb_node);
 525
 526         return next;
 527 }
 528
 529 static int btrfs_delayed_item_reserve_metadata(struct btrfs_trans_handle *trans,
 530                                                struct btrfs_fs_info *fs_info,
 531                                                struct btrfs_delayed_item *item)
 532 {
 533         struct btrfs_block_rsv *src_rsv;
 534         struct btrfs_block_rsv *dst_rsv;
 535         u64 num_bytes;
 536         int ret;
 537
 538         if (!trans->bytes_reserved)
 539                 return 0;
 540
 541         src_rsv = trans->block_rsv;
 542         dst_rsv = &fs_info->delayed_block_rsv;
 543
 544         num_bytes = btrfs_calc_trans_metadata_size(fs_info, 1);
 545         ret = btrfs_block_rsv_migrate(src_rsv, dst_rsv, num_bytes, 1);
 546         if (!ret) {
 547                 trace_btrfs_space_reservation(fs_info, "delayed_item",
 548                                               item->key.objectid,
 549                                               num_bytes, 1);
 550                 item->bytes_reserved = num_bytes;
 551         }
 552
 553         return ret;
 554 }
 555
 556 static void btrfs_delayed_item_release_metadata(struct btrfs_fs_info *fs_info,
 557                                                 struct btrfs_delayed_item *item)
 558 {
 559         struct btrfs_block_rsv *rsv;
 560
 561         if (!item->bytes_reserved)
 562                 return;
 563
 564         rsv = &fs_info->delayed_block_rsv;
 565         trace_btrfs_space_reservation(fs_info, "delayed_item",
 566                                       item->key.objectid, item->bytes_reserved,
 567                                       0);
 568         btrfs_block_rsv_release(fs_info, rsv,
 569                                 item->bytes_reserved);
 570 }
 571
 572 static int btrfs_delayed_inode_reserve_metadata(
 573                                         struct btrfs_trans_handle *trans,
 574                                         struct btrfs_root *root,
 575                                         struct btrfs_inode *inode,
 576                                         struct btrfs_delayed_node *node)
 577 {
 578         struct btrfs_fs_info *fs_info = root->fs_info;
 579         struct btrfs_block_rsv *src_rsv;
 580         struct btrfs_block_rsv *dst_rsv;
 581         u64 num_bytes;
 582         int ret;
 583         bool release = false;
 584
 585         src_rsv = trans->block_rsv;
 586         dst_rsv = &fs_info->delayed_block_rsv;
 587
 588         num_bytes = btrfs_calc_trans_metadata_size(fs_info, 1);
 589
 590         /*
 591          * If our block_rsv is the delalloc block reserve then check and see if
 592          * we have our extra reservation for updating the inode.  If not fall
 593          * through and try to reserve space quickly.
 594          *
 595          * We used to try and steal from the delalloc block rsv or the global
 596          * reserve, but we'd steal a full reservation, which isn't kind.  We are
 597          * here through delalloc which means we've likely just cowed down close
 598          * to the leaf that contains the inode, so we would steal less just
 599          * doing the fallback inode update, so if we do end up having to steal
 600          * from the global block rsv we hopefully only steal one or two blocks
 601          * worth which is less likely to hurt us.
 602          */
 603         if (src_rsv && src_rsv->type == BTRFS_BLOCK_RSV_DELALLOC) {
 604                 spin_lock(&inode->lock);
 605                 if (test_and_clear_bit(BTRFS_INODE_DELALLOC_META_RESERVED,
 606                                        &inode->runtime_flags))
 607                         release = true;
 608                 else
 609                         src_rsv = NULL;
 610                 spin_unlock(&inode->lock);
 611         }
 612
 613         /*
 614          * btrfs_dirty_inode will update the inode under btrfs_join_transaction
 615          * which doesn't reserve space for speed.  This is a problem since we
 616          * still need to reserve space for this update, so try to reserve the
 617          * space.
 618          *
 619          * Now if src_rsv == delalloc_block_rsv we'll let it just steal since
 620          * we're accounted for.
 621          */
 622         if (!src_rsv || (!trans->bytes_reserved &&
 623                          src_rsv->type != BTRFS_BLOCK_RSV_DELALLOC)) {
 624                 ret = btrfs_block_rsv_add(root, dst_rsv, num_bytes,
 625                                           BTRFS_RESERVE_NO_FLUSH);
 626                 /*
 627                  * Since we're under a transaction reserve_metadata_bytes could
 628                  * try to commit the transaction which will make it return
 629                  * EAGAIN to make us stop the transaction we have, so return
 630                  * ENOSPC instead so that btrfs_dirty_inode knows what to do.
 631                  */
 632                 if (ret == -EAGAIN)
 633                         ret = -ENOSPC;
 634                 if (!ret) {
 635                         node->bytes_reserved = num_bytes;
 636                         trace_btrfs_space_reservation(fs_info,
 637                                                       "delayed_inode",
 638                                                       btrfs_ino(inode),
 639                                                       num_bytes, 1);
 640                 }
 641                 return ret;
 642         }
 643
 644         ret = btrfs_block_rsv_migrate(src_rsv, dst_rsv, num_bytes, 1);
 645
 646         /*
 647          * Migrate only takes a reservation, it doesn't touch the size of the
 648          * block_rsv.  This is to simplify people who don't normally have things
 649          * migrated from their block rsv.  If they go to release their
 650          * reservation, that will decrease the size as well, so if migrate
 651          * reduced size we'd end up with a negative size.  But for the
 652          * delalloc_meta_reserved stuff we will only know to drop 1 reservation,
 653          * but we could in fact do this reserve/migrate dance several times
 654          * between the time we did the original reservation and we'd clean it
 655          * up.  So to take care of this, release the space for the meta
 656          * reservation here.  I think it may be time for a documentation page on
 657          * how block rsvs. work.
 658          */
 659         if (!ret) {
 660                 trace_btrfs_space_reservation(fs_info, "delayed_inode",
 661                                               btrfs_ino(inode), num_bytes, 1);
 662                 node->bytes_reserved = num_bytes;
 663         }
 664
 665         if (release) {
 666                 trace_btrfs_space_reservation(fs_info, "delalloc",
 667                                               btrfs_ino(inode), num_bytes, 0);
 668                 btrfs_block_rsv_release(fs_info, src_rsv, num_bytes);
 669         }
 670
 671         return ret;
 672 }
 673
 674 static void btrfs_delayed_inode_release_metadata(struct btrfs_fs_info *fs_info,
 675                                                 struct btrfs_delayed_node *node)
 676 {
 677         struct btrfs_block_rsv *rsv;
 678
 679         if (!node->bytes_reserved)
 680                 return;
 681
 682         rsv = &fs_info->delayed_block_rsv;
 683         trace_btrfs_space_reservation(fs_info, "delayed_inode",
 684                                       node->inode_id, node->bytes_reserved, 0);
 685         btrfs_block_rsv_release(fs_info, rsv,
 686                                 node->bytes_reserved);
 687         node->bytes_reserved = 0;
 688 }
 689
 690 /*
 691  * This helper will insert some continuous items into the same leaf according
 692  * to the free space of the leaf.
 693  */
 694 static int btrfs_batch_insert_items(struct btrfs_root *root,
 695                                     struct btrfs_path *path,
 696                                     struct btrfs_delayed_item *item)
 697 {
 698         struct btrfs_fs_info *fs_info = root->fs_info;
 699         struct btrfs_delayed_item *curr, *next;
 700         int free_space;
 701         int total_data_size = 0, total_size = 0;
 702         struct extent_buffer *leaf;
 703         char *data_ptr;
 704         struct btrfs_key *keys;
 705         u32 *data_size;
 706         struct list_head head;
 707         int slot;
 708         int nitems;
 709         int i;
 710         int ret = 0;
 711
 712         BUG_ON(!path->nodes[0]);
 713
 714         leaf = path->nodes[0];
 715         free_space = btrfs_leaf_free_space(fs_info, leaf);
 716         INIT_LIST_HEAD(&head);
 717
 718         next = item;
 719         nitems = 0;
 720
 721         /*
 722          * count the number of the continuous items that we can insert in batch
 723          */
 724         while (total_size + next->data_len + sizeof(struct btrfs_item) <=
 725                free_space) {
 726                 total_data_size += next->data_len;
 727                 total_size += next->data_len + sizeof(struct btrfs_item);
 728                 list_add_tail(&next->tree_list, &head);
 729                 nitems++;
 730
 731                 curr = next;
 732                 next = __btrfs_next_delayed_item(curr);
 733                 if (!next)
 734                         break;
 735
 736                 if (!btrfs_is_continuous_delayed_item(curr, next))
 737                         break;
 738         }
 739
 740         if (!nitems) {
 741                 ret = 0;
 742                 goto out;
 743         }
 744
 745         /*
 746          * we need allocate some memory space, but it might cause the task
 747          * to sleep, so we set all locked nodes in the path to blocking locks
 748          * first.
 749          */
 750         btrfs_set_path_blocking(path);
 751
 752         keys = kmalloc_array(nitems, sizeof(struct btrfs_key), GFP_NOFS);
 753         if (!keys) {
 754                 ret = -ENOMEM;
 755                 goto out;
 756         }
 757
 758         data_size = kmalloc_array(nitems, sizeof(u32), GFP_NOFS);
 759         if (!data_size) {
 760                 ret = -ENOMEM;
 761                 goto error;
 762         }
 763
 764         /* get keys of all the delayed items */
 765         i = 0;
 766         list_for_each_entry(next, &head, tree_list) {
 767                 keys[i] = next->key;
 768                 data_size[i] = next->data_len;
 769                 i++;
 770         }
 771
 772         /* reset all the locked nodes in the patch to spinning locks. */
 773         btrfs_clear_path_blocking(path, NULL, 0);
 774
 775         /* insert the keys of the items */
 776         setup_items_for_insert(root, path, keys, data_size,
 777                                total_data_size, total_size, nitems);
 778
 779         /* insert the dir index items */
 780         slot = path->slots[0];
 781         list_for_each_entry_safe(curr, next, &head, tree_list) {
 782                 data_ptr = btrfs_item_ptr(leaf, slot, char);
 783                 write_extent_buffer(leaf, &curr->data,
 784                                     (unsigned long)data_ptr,
 785                                     curr->data_len);
 786                 slot++;
 787
 788                 btrfs_delayed_item_release_metadata(fs_info, curr);
 789
 790                 list_del(&curr->tree_list);
 791                 btrfs_release_delayed_item(curr);
 792         }
 793
 794 error:
 795         kfree(data_size);
 796         kfree(keys);
 797 out:
 798         return ret;
 799 }
 800
 801 /*
 802  * This helper can just do simple insertion that needn't extend item for new
 803  * data, such as directory name index insertion, inode insertion.
 804  */
 805 static int btrfs_insert_delayed_item(struct btrfs_trans_handle *trans,
 806                                      struct btrfs_root *root,
 807                                      struct btrfs_path *path,
 808                                      struct btrfs_delayed_item *delayed_item)
 809 {
 810         struct btrfs_fs_info *fs_info = root->fs_info;
 811         struct extent_buffer *leaf;
 812         char *ptr;
 813         int ret;
 814
 815         ret = btrfs_insert_empty_item(trans, root, path, &delayed_item->key,
 816                                       delayed_item->data_len);
 817         if (ret < 0 && ret != -EEXIST)
 818                 return ret;
 819
 820         leaf = path->nodes[0];
 821
 822         ptr = btrfs_item_ptr(leaf, path->slots[0], char);
 823
 824         write_extent_buffer(leaf, delayed_item->data, (unsigned long)ptr,
 825                             delayed_item->data_len);
 826         btrfs_mark_buffer_dirty(leaf);
 827
 828         btrfs_delayed_item_release_metadata(fs_info, delayed_item);
 829         return 0;
 830 }
 831
 832 /*
 833  * we insert an item first, then if there are some continuous items, we try
 834  * to insert those items into the same leaf.
 835  */
 836 static int btrfs_insert_delayed_items(struct btrfs_trans_handle *trans,
 837                                       struct btrfs_path *path,
 838                                       struct btrfs_root *root,
 839                                       struct btrfs_delayed_node *node)
 840 {
 841         struct btrfs_delayed_item *curr, *prev;
 842         int ret = 0;
 843
 844 do_again:
 845         mutex_lock(&node->mutex);
 846         curr = __btrfs_first_delayed_insertion_item(node);
 847         if (!curr)
 848                 goto insert_end;
 849
 850         ret = btrfs_insert_delayed_item(trans, root, path, curr);
 851         if (ret < 0) {
 852                 btrfs_release_path(path);
 853                 goto insert_end;
 854         }
 855
 856         prev = curr;
 857         curr = __btrfs_next_delayed_item(prev);
 858         if (curr && btrfs_is_continuous_delayed_item(prev, curr)) {
 859                 /* insert the continuous items into the same leaf */
 860                 path->slots[0]++;
 861                 btrfs_batch_insert_items(root, path, curr);
 862         }
 863         btrfs_release_delayed_item(prev);
 864         btrfs_mark_buffer_dirty(path->nodes[0]);
 865
 866         btrfs_release_path(path);
 867         mutex_unlock(&node->mutex);
 868         goto do_again;
 869
 870 insert_end:
 871         mutex_unlock(&node->mutex);
 872         return ret;
 873 }
 874
 875 static int btrfs_batch_delete_items(struct btrfs_trans_handle *trans,
 876                                     struct btrfs_root *root,
 877                                     struct btrfs_path *path,
 878                                     struct btrfs_delayed_item *item)
 879 {
 880         struct btrfs_fs_info *fs_info = root->fs_info;
 881         struct btrfs_delayed_item *curr, *next;
 882         struct extent_buffer *leaf;
 883         struct btrfs_key key;
 884         struct list_head head;
 885         int nitems, i, last_item;
 886         int ret = 0;
 887
 888         BUG_ON(!path->nodes[0]);
 889
 890         leaf = path->nodes[0];
 891
 892         i = path->slots[0];
 893         last_item = btrfs_header_nritems(leaf) - 1;
 894         if (i > last_item)
 895                 return -ENOENT; /* FIXME: Is errno suitable? */
 896
 897         next = item;
 898         INIT_LIST_HEAD(&head);
 899         btrfs_item_key_to_cpu(leaf, &key, i);
 900         nitems = 0;
 901         /*
 902          * count the number of the dir index items that we can delete in batch
 903          */
 904         while (btrfs_comp_cpu_keys(&next->key, &key) == 0) {
 905                 list_add_tail(&next->tree_list, &head);
 906                 nitems++;
 907
 908                 curr = next;
 909                 next = __btrfs_next_delayed_item(curr);
 910                 if (!next)
 911                         break;
 912
 913                 if (!btrfs_is_continuous_delayed_item(curr, next))
 914                         break;
 915
 916                 i++;
 917                 if (i > last_item)
 918                         break;
 919                 btrfs_item_key_to_cpu(leaf, &key, i);
 920         }
 921
 922         if (!nitems)
 923                 return 0;
 924
 925         ret = btrfs_del_items(trans, root, path, path->slots[0], nitems);
 926         if (ret)
 927                 goto out;
 928
 929         list_for_each_entry_safe(curr, next, &head, tree_list) {
 930                 btrfs_delayed_item_release_metadata(fs_info, curr);
 931                 list_del(&curr->tree_list);
 932                 btrfs_release_delayed_item(curr);
 933         }
 934
 935 out:
 936         return ret;
 937 }
 938
 939 static int btrfs_delete_delayed_items(struct btrfs_trans_handle *trans,
 940                                       struct btrfs_path *path,
 941                                       struct btrfs_root *root,
 942                                       struct btrfs_delayed_node *node)
 943 {
 944         struct btrfs_delayed_item *curr, *prev;
 945         int ret = 0;
 946
 947 do_again:
 948         mutex_lock(&node->mutex);
 949         curr = __btrfs_first_delayed_deletion_item(node);
 950         if (!curr)
 951                 goto delete_fail;
 952
 953         ret = btrfs_search_slot(trans, root, &curr->key, path, -1, 1);
 954         if (ret < 0)
 955                 goto delete_fail;
 956         else if (ret > 0) {
 957                 /*
 958                  * can't find the item which the node points to, so this node
 959                  * is invalid, just drop it.
 960                  */
 961                 prev = curr;
 962                 curr = __btrfs_next_delayed_item(prev);
 963                 btrfs_release_delayed_item(prev);
 964                 ret = 0;
 965                 btrfs_release_path(path);
 966                 if (curr) {
 967                         mutex_unlock(&node->mutex);
 968                         goto do_again;
 969                 } else
 970                         goto delete_fail;
 971         }
 972
 973         btrfs_batch_delete_items(trans, root, path, curr);
 974         btrfs_release_path(path);
 975         mutex_unlock(&node->mutex);
 976         goto do_again;
 977
 978 delete_fail:
 979         btrfs_release_path(path);
 980         mutex_unlock(&node->mutex);
 981         return ret;
 982 }
 983
 984 static void btrfs_release_delayed_inode(struct btrfs_delayed_node *delayed_node)
 985 {
 986         struct btrfs_delayed_root *delayed_root;
 987
 988         if (delayed_node &&
 989             test_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags)) {
 990                 BUG_ON(!delayed_node->root);
 991                 clear_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags);
 992                 delayed_node->count--;
 993
 994                 delayed_root = delayed_node->root->fs_info->delayed_root;
 995                 finish_one_item(delayed_root);
 996         }
 997 }
 998
 999 static void btrfs_release_delayed_iref(struct btrfs_delayed_node *delayed_node)
1000 {
1001         struct btrfs_delayed_root *delayed_root;
1002
1003         ASSERT(delayed_node->root);
1004         clear_bit(BTRFS_DELAYED_NODE_DEL_IREF, &delayed_node->flags);
1005         delayed_node->count--;
1006
1007         delayed_root = delayed_node->root->fs_info->delayed_root;
1008         finish_one_item(delayed_root);
1009 }
1010
1011 static int __btrfs_update_delayed_inode(struct btrfs_trans_handle *trans,
1012                                         struct btrfs_root *root,
1013                                         struct btrfs_path *path,
1014                                         struct btrfs_delayed_node *node)
1015 {
1016         struct btrfs_fs_info *fs_info = root->fs_info;
1017         struct btrfs_key key;
1018         struct btrfs_inode_item *inode_item;
1019         struct extent_buffer *leaf;
1020         int mod;
1021         int ret;
1022
1023         key.objectid = node->inode_id;
1024         key.type = BTRFS_INODE_ITEM_KEY;
1025         key.offset = 0;
1026
1027         if (test_bit(BTRFS_DELAYED_NODE_DEL_IREF, &node->flags))
1028                 mod = -1;
1029         else
1030                 mod = 1;
1031
1032         ret = btrfs_lookup_inode(trans, root, path, &key, mod);
1033         if (ret > 0) {
1034                 btrfs_release_path(path);
1035                 return -ENOENT;
1036         } else if (ret < 0) {
1037                 return ret;
1038         }
1039
1040         leaf = path->nodes[0];
1041         inode_item = btrfs_item_ptr(leaf, path->slots[0],
1042                                     struct btrfs_inode_item);
1043         write_extent_buffer(leaf, &node->inode_item, (unsigned long)inode_item,
1044                             sizeof(struct btrfs_inode_item));
1045         btrfs_mark_buffer_dirty(leaf);
1046
1047         if (!test_bit(BTRFS_DELAYED_NODE_DEL_IREF, &node->flags))
1048                 goto no_iref;
1049
1050         path->slots[0]++;
1051         if (path->slots[0] >= btrfs_header_nritems(leaf))
1052                 goto search;
1053 again:
1054         btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1055         if (key.objectid != node->inode_id)
1056                 goto out;
1057
1058         if (key.type != BTRFS_INODE_REF_KEY &&
1059             key.type != BTRFS_INODE_EXTREF_KEY)
1060                 goto out;
1061
1062         /*
1063          * Delayed iref deletion is for the inode who has only one link,
1064          * so there is only one iref. The case that several irefs are
1065          * in the same item doesn't exist.
1066          */
1067         btrfs_del_item(trans, root, path);
1068 out:
1069         btrfs_release_delayed_iref(node);
1070 no_iref:
1071         btrfs_release_path(path);
1072 err_out:
1073         btrfs_delayed_inode_release_metadata(fs_info, node);
1074         btrfs_release_delayed_inode(node);
1075
1076         return ret;
1077
1078 search:
1079         btrfs_release_path(path);
1080
1081         key.type = BTRFS_INODE_EXTREF_KEY;
1082         key.offset = -1;
1083         ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1084         if (ret < 0)
1085                 goto err_out;
1086         ASSERT(ret);
1087
1088         ret = 0;
1089         leaf = path->nodes[0];
1090         path->slots[0]--;
1091         goto again;
1092 }
1093
1094 static inline int btrfs_update_delayed_inode(struct btrfs_trans_handle *trans,
1095                                              struct btrfs_root *root,
1096                                              struct btrfs_path *path,
1097                                              struct btrfs_delayed_node *node)
1098 {
1099         int ret;
1100
1101         mutex_lock(&node->mutex);
1102         if (!test_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &node->flags)) {
1103                 mutex_unlock(&node->mutex);
1104                 return 0;
1105         }
1106
1107         ret = __btrfs_update_delayed_inode(trans, root, path, node);
1108         mutex_unlock(&node->mutex);
1109         return ret;
1110 }
1111
1112 static inline int
1113 __btrfs_commit_inode_delayed_items(struct btrfs_trans_handle *trans,
1114                                    struct btrfs_path *path,
1115                                    struct btrfs_delayed_node *node)
1116 {
1117         int ret;
1118
1119         ret = btrfs_insert_delayed_items(trans, path, node->root, node);
1120         if (ret)
1121                 return ret;
1122
1123         ret = btrfs_delete_delayed_items(trans, path, node->root, node);
1124         if (ret)
1125                 return ret;
1126
1127         ret = btrfs_update_delayed_inode(trans, node->root, path, node);
1128         return ret;
1129 }
1130
1131 /*
1132  * Called when committing the transaction.
1133  * Returns 0 on success.
1134  * Returns < 0 on error and returns with an aborted transaction with any
1135  * outstanding delayed items cleaned up.
1136  */
1137 static int __btrfs_run_delayed_items(struct btrfs_trans_handle *trans,
1138                                      struct btrfs_fs_info *fs_info, int nr)
1139 {
1140         struct btrfs_delayed_root *delayed_root;
1141         struct btrfs_delayed_node *curr_node, *prev_node;
1142         struct btrfs_path *path;
1143         struct btrfs_block_rsv *block_rsv;
1144         int ret = 0;
1145         bool count = (nr > 0);
1146
1147         if (trans->aborted)
1148                 return -EIO;
1149
1150         path = btrfs_alloc_path();
1151         if (!path)
1152                 return -ENOMEM;
1153         path->leave_spinning = 1;
1154
1155         block_rsv = trans->block_rsv;
1156         trans->block_rsv = &fs_info->delayed_block_rsv;
1157
1158         delayed_root = fs_info->delayed_root;
1159
1160         curr_node = btrfs_first_delayed_node(delayed_root);
1161         while (curr_node && (!count || (count && nr--))) {
1162                 ret = __btrfs_commit_inode_delayed_items(trans, path,
1163                                                          curr_node);
1164                 if (ret) {
1165                         btrfs_release_delayed_node(curr_node);
1166                         curr_node = NULL;
1167                         btrfs_abort_transaction(trans, ret);
1168                         break;
1169                 }
1170
1171                 prev_node = curr_node;
1172                 curr_node = btrfs_next_delayed_node(curr_node);
1173                 btrfs_release_delayed_node(prev_node);
1174         }
1175
1176         if (curr_node)
1177                 btrfs_release_delayed_node(curr_node);
1178         btrfs_free_path(path);
1179         trans->block_rsv = block_rsv;
1180
1181         return ret;
1182 }
1183
1184 int btrfs_run_delayed_items(struct btrfs_trans_handle *trans,
1185                             struct btrfs_fs_info *fs_info)
1186 {
1187         return __btrfs_run_delayed_items(trans, fs_info, -1);
1188 }
1189
1190 int btrfs_run_delayed_items_nr(struct btrfs_trans_handle *trans,
1191                                struct btrfs_fs_info *fs_info, int nr)
1192 {
1193         return __btrfs_run_delayed_items(trans, fs_info, nr);
1194 }
1195
1196 int btrfs_commit_inode_delayed_items(struct btrfs_trans_handle *trans,
1197                                      struct inode *inode)
1198 {
1199         struct btrfs_delayed_node *delayed_node = btrfs_get_delayed_node(BTRFS_I(inode));
1200         struct btrfs_path *path;
1201         struct btrfs_block_rsv *block_rsv;
1202         int ret;
1203
1204         if (!delayed_node)
1205                 return 0;
1206
1207         mutex_lock(&delayed_node->mutex);
1208         if (!delayed_node->count) {
1209                 mutex_unlock(&delayed_node->mutex);
1210                 btrfs_release_delayed_node(delayed_node);
1211                 return 0;
1212         }
1213         mutex_unlock(&delayed_node->mutex);
1214
1215         path = btrfs_alloc_path();
1216         if (!path) {
1217                 btrfs_release_delayed_node(delayed_node);
1218                 return -ENOMEM;
1219         }
1220         path->leave_spinning = 1;
1221
1222         block_rsv = trans->block_rsv;
1223         trans->block_rsv = &delayed_node->root->fs_info->delayed_block_rsv;
1224
1225         ret = __btrfs_commit_inode_delayed_items(trans, path, delayed_node);
1226
1227         btrfs_release_delayed_node(delayed_node);
1228         btrfs_free_path(path);
1229         trans->block_rsv = block_rsv;
1230
1231         return ret;
1232 }
1233
1234 int btrfs_commit_inode_delayed_inode(struct inode *inode)
1235 {
1236         struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1237         struct btrfs_trans_handle *trans;
1238         struct btrfs_delayed_node *delayed_node = btrfs_get_delayed_node(BTRFS_I(inode));
1239         struct btrfs_path *path;
1240         struct btrfs_block_rsv *block_rsv;
1241         int ret;
1242
1243         if (!delayed_node)
1244                 return 0;
1245
1246         mutex_lock(&delayed_node->mutex);
1247         if (!test_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags)) {
1248                 mutex_unlock(&delayed_node->mutex);
1249                 btrfs_release_delayed_node(delayed_node);
1250                 return 0;
1251         }
1252         mutex_unlock(&delayed_node->mutex);
1253
1254         trans = btrfs_join_transaction(delayed_node->root);
1255         if (IS_ERR(trans)) {
1256                 ret = PTR_ERR(trans);
1257                 goto out;
1258         }
1259
1260         path = btrfs_alloc_path();
1261         if (!path) {
1262                 ret = -ENOMEM;
1263                 goto trans_out;
1264         }
1265         path->leave_spinning = 1;
1266
1267         block_rsv = trans->block_rsv;
1268         trans->block_rsv = &fs_info->delayed_block_rsv;
1269
1270         mutex_lock(&delayed_node->mutex);
1271         if (test_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags))
1272                 ret = __btrfs_update_delayed_inode(trans, delayed_node->root,
1273                                                    path, delayed_node);
1274         else
1275                 ret = 0;
1276         mutex_unlock(&delayed_node->mutex);
1277
1278         btrfs_free_path(path);
1279         trans->block_rsv = block_rsv;
1280 trans_out:
1281         btrfs_end_transaction(trans);
1282         btrfs_btree_balance_dirty(fs_info);
1283 out:
1284         btrfs_release_delayed_node(delayed_node);
1285
1286         return ret;
1287 }
1288
1289 void btrfs_remove_delayed_node(struct inode *inode)
1290 {
1291         struct btrfs_delayed_node *delayed_node;
1292
1293         delayed_node = READ_ONCE(BTRFS_I(inode)->delayed_node);
1294         if (!delayed_node)
1295                 return;
1296
1297         BTRFS_I(inode)->delayed_node = NULL;
1298         btrfs_release_delayed_node(delayed_node);
1299 }
1300
1301 struct btrfs_async_delayed_work {
1302         struct btrfs_delayed_root *delayed_root;
1303         int nr;
1304         struct btrfs_work work;
1305 };
1306
1307 static void btrfs_async_run_delayed_root(struct btrfs_work *work)
1308 {
1309         struct btrfs_async_delayed_work *async_work;
1310         struct btrfs_delayed_root *delayed_root;
1311         struct btrfs_trans_handle *trans;
1312         struct btrfs_path *path;
1313         struct btrfs_delayed_node *delayed_node = NULL;
1314         struct btrfs_root *root;
1315         struct btrfs_block_rsv *block_rsv;
1316         int total_done = 0;
1317
1318         async_work = container_of(work, struct btrfs_async_delayed_work, work);
1319         delayed_root = async_work->delayed_root;
1320
1321         path = btrfs_alloc_path();
1322         if (!path)
1323                 goto out;
1324
1325 again:
1326         if (atomic_read(&delayed_root->items) < BTRFS_DELAYED_BACKGROUND / 2)
1327                 goto free_path;
1328
1329         delayed_node = btrfs_first_prepared_delayed_node(delayed_root);
1330         if (!delayed_node)
1331                 goto free_path;
1332
1333         path->leave_spinning = 1;
1334         root = delayed_node->root;
1335
1336         trans = btrfs_join_transaction(root);
1337         if (IS_ERR(trans))
1338                 goto release_path;
1339
1340         block_rsv = trans->block_rsv;
1341         trans->block_rsv = &root->fs_info->delayed_block_rsv;
1342
1343         __btrfs_commit_inode_delayed_items(trans, path, delayed_node);
1344
1345         trans->block_rsv = block_rsv;
1346         btrfs_end_transaction(trans);
1347         btrfs_btree_balance_dirty_nodelay(root->fs_info);
1348
1349 release_path:
1350         btrfs_release_path(path);
1351         total_done++;
1352
1353         btrfs_release_prepared_delayed_node(delayed_node);
1354         if ((async_work->nr == 0 && total_done < BTRFS_DELAYED_WRITEBACK) ||
1355             total_done < async_work->nr)
1356                 goto again;
1357
1358 free_path:
1359         btrfs_free_path(path);
1360 out:
1361         wake_up(&delayed_root->wait);
1362         kfree(async_work);
1363 }
1364
1365
1366 static int btrfs_wq_run_delayed_node(struct btrfs_delayed_root *delayed_root,
1367                                      struct btrfs_fs_info *fs_info, int nr)
1368 {
1369         struct btrfs_async_delayed_work *async_work;
1370
1371         if (atomic_read(&delayed_root->items) < BTRFS_DELAYED_BACKGROUND ||
1372             btrfs_workqueue_normal_congested(fs_info->delayed_workers))
1373                 return 0;
1374
1375         async_work = kmalloc(sizeof(*async_work), GFP_NOFS);
1376         if (!async_work)
1377                 return -ENOMEM;
1378
1379         async_work->delayed_root = delayed_root;
1380         btrfs_init_work(&async_work->work, btrfs_delayed_meta_helper,
1381                         btrfs_async_run_delayed_root, NULL, NULL);
1382         async_work->nr = nr;
1383
1384         btrfs_queue_work(fs_info->delayed_workers, &async_work->work);
1385         return 0;
1386 }
1387
1388 void btrfs_assert_delayed_root_empty(struct btrfs_fs_info *fs_info)
1389 {
1390         WARN_ON(btrfs_first_delayed_node(fs_info->delayed_root));
1391 }
1392
1393 static int could_end_wait(struct btrfs_delayed_root *delayed_root, int seq)
1394 {
1395         int val = atomic_read(&delayed_root->items_seq);
1396
1397         if (val < seq || val >= seq + BTRFS_DELAYED_BATCH)
1398                 return 1;
1399
1400         if (atomic_read(&delayed_root->items) < BTRFS_DELAYED_BACKGROUND)
1401                 return 1;
1402
1403         return 0;
1404 }
1405
1406 void btrfs_balance_delayed_items(struct btrfs_fs_info *fs_info)
1407 {
1408         struct btrfs_delayed_root *delayed_root = fs_info->delayed_root;
1409
1410         if (atomic_read(&delayed_root->items) < BTRFS_DELAYED_BACKGROUND)
1411                 return;
1412
1413         if (atomic_read(&delayed_root->items) >= BTRFS_DELAYED_WRITEBACK) {
1414                 int seq;
1415                 int ret;
1416
1417                 seq = atomic_read(&delayed_root->items_seq);
1418
1419                 ret = btrfs_wq_run_delayed_node(delayed_root, fs_info, 0);
1420                 if (ret)
1421                         return;
1422
1423                 wait_event_interruptible(delayed_root->wait,
1424                                          could_end_wait(delayed_root, seq));
1425                 return;
1426         }
1427
1428         btrfs_wq_run_delayed_node(delayed_root, fs_info, BTRFS_DELAYED_BATCH);
1429 }
1430
1431 /* Will return 0 or -ENOMEM */
1432 int btrfs_insert_delayed_dir_index(struct btrfs_trans_handle *trans,
1433                                    struct btrfs_fs_info *fs_info,
1434                                    const char *name, int name_len,
1435                                    struct btrfs_inode *dir,
1436                                    struct btrfs_disk_key *disk_key, u8 type,
1437                                    u64 index)
1438 {
1439         struct btrfs_delayed_node *delayed_node;
1440         struct btrfs_delayed_item *delayed_item;
1441         struct btrfs_dir_item *dir_item;
1442         int ret;
1443
1444         delayed_node = btrfs_get_or_create_delayed_node(dir);
1445         if (IS_ERR(delayed_node))
1446                 return PTR_ERR(delayed_node);
1447
1448         delayed_item = btrfs_alloc_delayed_item(sizeof(*dir_item) + name_len);
1449         if (!delayed_item) {
1450                 ret = -ENOMEM;
1451                 goto release_node;
1452         }
1453
1454         delayed_item->key.objectid = btrfs_ino(dir);
1455         delayed_item->key.type = BTRFS_DIR_INDEX_KEY;
1456         delayed_item->key.offset = index;
1457
1458         dir_item = (struct btrfs_dir_item *)delayed_item->data;
1459         dir_item->location = *disk_key;
1460         btrfs_set_stack_dir_transid(dir_item, trans->transid);
1461         btrfs_set_stack_dir_data_len(dir_item, 0);
1462         btrfs_set_stack_dir_name_len(dir_item, name_len);
1463         btrfs_set_stack_dir_type(dir_item, type);
1464         memcpy((char *)(dir_item + 1), name, name_len);
1465
1466         ret = btrfs_delayed_item_reserve_metadata(trans, fs_info, delayed_item);
1467         /*
1468          * we have reserved enough space when we start a new transaction,
1469          * so reserving metadata failure is impossible
1470          */
1471         BUG_ON(ret);
1472
1473
1474         mutex_lock(&delayed_node->mutex);
1475         ret = __btrfs_add_delayed_insertion_item(delayed_node, delayed_item);
1476         if (unlikely(ret)) {
1477                 btrfs_err(fs_info,
1478                           "err add delayed dir index item(name: %.*s) into the insertion tree of the delayed node(root id: %llu, inode id: %llu, errno: %d)",
1479                           name_len, name, delayed_node->root->objectid,
1480                           delayed_node->inode_id, ret);
1481                 BUG();
1482         }
1483         mutex_unlock(&delayed_node->mutex);
1484
1485 release_node:
1486         btrfs_release_delayed_node(delayed_node);
1487         return ret;
1488 }
1489
1490 static int btrfs_delete_delayed_insertion_item(struct btrfs_fs_info *fs_info,
1491                                                struct btrfs_delayed_node *node,
1492                                                struct btrfs_key *key)
1493 {
1494         struct btrfs_delayed_item *item;
1495
1496         mutex_lock(&node->mutex);
1497         item = __btrfs_lookup_delayed_insertion_item(node, key);
1498         if (!item) {
1499                 mutex_unlock(&node->mutex);
1500                 return 1;
1501         }
1502
1503         btrfs_delayed_item_release_metadata(fs_info, item);
1504         btrfs_release_delayed_item(item);
1505         mutex_unlock(&node->mutex);
1506         return 0;
1507 }
1508
1509 int btrfs_delete_delayed_dir_index(struct btrfs_trans_handle *trans,
1510                                    struct btrfs_fs_info *fs_info,
1511                                    struct btrfs_inode *dir, u64 index)
1512 {
1513         struct btrfs_delayed_node *node;
1514         struct btrfs_delayed_item *item;
1515         struct btrfs_key item_key;
1516         int ret;
1517
1518         node = btrfs_get_or_create_delayed_node(dir);
1519         if (IS_ERR(node))
1520                 return PTR_ERR(node);
1521
1522         item_key.objectid = btrfs_ino(dir);
1523         item_key.type = BTRFS_DIR_INDEX_KEY;
1524         item_key.offset = index;
1525
1526         ret = btrfs_delete_delayed_insertion_item(fs_info, node, &item_key);
1527         if (!ret)
1528                 goto end;
1529
1530         item = btrfs_alloc_delayed_item(0);
1531         if (!item) {
1532                 ret = -ENOMEM;
1533                 goto end;
1534         }
1535
1536         item->key = item_key;
1537
1538         ret = btrfs_delayed_item_reserve_metadata(trans, fs_info, item);
1539         /*
1540          * we have reserved enough space when we start a new transaction,
1541          * so reserving metadata failure is impossible.
1542          */
1543         BUG_ON(ret);
1544
1545         mutex_lock(&node->mutex);
1546         ret = __btrfs_add_delayed_deletion_item(node, item);
1547         if (unlikely(ret)) {
1548                 btrfs_err(fs_info,
1549                           "err add delayed dir index item(index: %llu) into the deletion tree of the delayed node(root id: %llu, inode id: %llu, errno: %d)",
1550                           index, node->root->objectid, node->inode_id, ret);
1551                 BUG();
1552         }
1553         mutex_unlock(&node->mutex);
1554 end:
1555         btrfs_release_delayed_node(node);
1556         return ret;
1557 }
1558
1559 int btrfs_inode_delayed_dir_index_count(struct inode *inode)
1560 {
1561         struct btrfs_delayed_node *delayed_node = btrfs_get_delayed_node(BTRFS_I(inode));
1562
1563         if (!delayed_node)
1564                 return -ENOENT;
1565
1566         /*
1567          * Since we have held i_mutex of this directory, it is impossible that
1568          * a new directory index is added into the delayed node and index_cnt
1569          * is updated now. So we needn't lock the delayed node.
1570          */
1571         if (!delayed_node->index_cnt) {
1572                 btrfs_release_delayed_node(delayed_node);
1573                 return -EINVAL;
1574         }
1575
1576         BTRFS_I(inode)->index_cnt = delayed_node->index_cnt;
1577         btrfs_release_delayed_node(delayed_node);
1578         return 0;
1579 }
1580
1581 bool btrfs_readdir_get_delayed_items(struct inode *inode,
1582                                      struct list_head *ins_list,
1583                                      struct list_head *del_list)
1584 {
1585         struct btrfs_delayed_node *delayed_node;
1586         struct btrfs_delayed_item *item;
1587
1588         delayed_node = btrfs_get_delayed_node(BTRFS_I(inode));
1589         if (!delayed_node)
1590                 return false;
1591
1592         /*
1593          * We can only do one readdir with delayed items at a time because of
1594          * item->readdir_list.
1595          */
1596         inode_unlock_shared(inode);
1597         inode_lock(inode);
1598
1599         mutex_lock(&delayed_node->mutex);
1600         item = __btrfs_first_delayed_insertion_item(delayed_node);
1601         while (item) {
1602                 atomic_inc(&item->refs);
1603                 list_add_tail(&item->readdir_list, ins_list);
1604                 item = __btrfs_next_delayed_item(item);
1605         }
1606
1607         item = __btrfs_first_delayed_deletion_item(delayed_node);
1608         while (item) {
1609                 atomic_inc(&item->refs);
1610                 list_add_tail(&item->readdir_list, del_list);
1611                 item = __btrfs_next_delayed_item(item);
1612         }
1613         mutex_unlock(&delayed_node->mutex);
1614         /*
1615          * This delayed node is still cached in the btrfs inode, so refs
1616          * must be > 1 now, and we needn't check it is going to be freed
1617          * or not.
1618          *
1619          * Besides that, this function is used to read dir, we do not
1620          * insert/delete delayed items in this period. So we also needn't
1621          * requeue or dequeue this delayed node.
1622          */
1623         atomic_dec(&delayed_node->refs);
1624
1625         return true;
1626 }
1627
1628 void btrfs_readdir_put_delayed_items(struct inode *inode,
1629                                      struct list_head *ins_list,
1630                                      struct list_head *del_list)
1631 {
1632         struct btrfs_delayed_item *curr, *next;
1633
1634         list_for_each_entry_safe(curr, next, ins_list, readdir_list) {
1635                 list_del(&curr->readdir_list);
1636                 if (atomic_dec_and_test(&curr->refs))
1637                         kfree(curr);
1638         }
1639
1640         list_for_each_entry_safe(curr, next, del_list, readdir_list) {
1641                 list_del(&curr->readdir_list);
1642                 if (atomic_dec_and_test(&curr->refs))
1643                         kfree(curr);
1644         }
1645
1646         /*
1647          * The VFS is going to do up_read(), so we need to downgrade back to a
1648          * read lock.
1649          */
1650         downgrade_write(&inode->i_rwsem);
1651 }
1652
1653 int btrfs_should_delete_dir_index(struct list_head *del_list,
1654                                   u64 index)
1655 {
1656         struct btrfs_delayed_item *curr, *next;
1657         int ret;
1658
1659         if (list_empty(del_list))
1660                 return 0;
1661
1662         list_for_each_entry_safe(curr, next, del_list, readdir_list) {
1663                 if (curr->key.offset > index)
1664                         break;
1665
1666                 list_del(&curr->readdir_list);
1667                 ret = (curr->key.offset == index);
1668
1669                 if (atomic_dec_and_test(&curr->refs))
1670                         kfree(curr);
1671
1672                 if (ret)
1673                         return 1;
1674                 else
1675                         continue;
1676         }
1677         return 0;
1678 }
1679
1680 /*
1681  * btrfs_readdir_delayed_dir_index - read dir info stored in the delayed tree
1682  *
1683  */
1684 int btrfs_readdir_delayed_dir_index(struct dir_context *ctx,
1685                                     struct list_head *ins_list)
1686 {
1687         struct btrfs_dir_item *di;
1688         struct btrfs_delayed_item *curr, *next;
1689         struct btrfs_key location;
1690         char *name;
1691         int name_len;
1692         int over = 0;
1693         unsigned char d_type;
1694
1695         if (list_empty(ins_list))
1696                 return 0;
1697
1698         /*
1699          * Changing the data of the delayed item is impossible. So
1700          * we needn't lock them. And we have held i_mutex of the
1701          * directory, nobody can delete any directory indexes now.
1702          */
1703         list_for_each_entry_safe(curr, next, ins_list, readdir_list) {
1704                 list_del(&curr->readdir_list);
1705
1706                 if (curr->key.offset < ctx->pos) {
1707                         if (atomic_dec_and_test(&curr->refs))
1708                                 kfree(curr);
1709                         continue;
1710                 }
1711
1712                 ctx->pos = curr->key.offset;
1713
1714                 di = (struct btrfs_dir_item *)curr->data;
1715                 name = (char *)(di + 1);
1716                 name_len = btrfs_stack_dir_name_len(di);
1717
1718                 d_type = btrfs_filetype_table[di->type];
1719                 btrfs_disk_key_to_cpu(&location, &di->location);
1720
1721                 over = !dir_emit(ctx, name, name_len,
1722                                location.objectid, d_type);
1723
1724                 if (atomic_dec_and_test(&curr->refs))
1725                         kfree(curr);
1726
1727                 if (over)
1728                         return 1;
1729         }
1730         return 0;
1731 }
1732
1733 static void fill_stack_inode_item(struct btrfs_trans_handle *trans,
1734                                   struct btrfs_inode_item *inode_item,
1735                                   struct inode *inode)
1736 {
1737         btrfs_set_stack_inode_uid(inode_item, i_uid_read(inode));
1738         btrfs_set_stack_inode_gid(inode_item, i_gid_read(inode));
1739         btrfs_set_stack_inode_size(inode_item, BTRFS_I(inode)->disk_i_size);
1740         btrfs_set_stack_inode_mode(inode_item, inode->i_mode);
1741         btrfs_set_stack_inode_nlink(inode_item, inode->i_nlink);
1742         btrfs_set_stack_inode_nbytes(inode_item, inode_get_bytes(inode));
1743         btrfs_set_stack_inode_generation(inode_item,
1744                                          BTRFS_I(inode)->generation);
1745         btrfs_set_stack_inode_sequence(inode_item, inode->i_version);
1746         btrfs_set_stack_inode_transid(inode_item, trans->transid);
1747         btrfs_set_stack_inode_rdev(inode_item, inode->i_rdev);
1748         btrfs_set_stack_inode_flags(inode_item, BTRFS_I(inode)->flags);
1749         btrfs_set_stack_inode_block_group(inode_item, 0);
1750
1751         btrfs_set_stack_timespec_sec(&inode_item->atime,
1752                                      inode->i_atime.tv_sec);
1753         btrfs_set_stack_timespec_nsec(&inode_item->atime,
1754                                       inode->i_atime.tv_nsec);
1755
1756         btrfs_set_stack_timespec_sec(&inode_item->mtime,
1757                                      inode->i_mtime.tv_sec);
1758         btrfs_set_stack_timespec_nsec(&inode_item->mtime,
1759                                       inode->i_mtime.tv_nsec);
1760
1761         btrfs_set_stack_timespec_sec(&inode_item->ctime,
1762                                      inode->i_ctime.tv_sec);
1763         btrfs_set_stack_timespec_nsec(&inode_item->ctime,
1764                                       inode->i_ctime.tv_nsec);
1765
1766         btrfs_set_stack_timespec_sec(&inode_item->otime,
1767                                      BTRFS_I(inode)->i_otime.tv_sec);
1768         btrfs_set_stack_timespec_nsec(&inode_item->otime,
1769                                      BTRFS_I(inode)->i_otime.tv_nsec);
1770 }
1771
1772 int btrfs_fill_inode(struct inode *inode, u32 *rdev)
1773 {
1774         struct btrfs_delayed_node *delayed_node;
1775         struct btrfs_inode_item *inode_item;
1776
1777         delayed_node = btrfs_get_delayed_node(BTRFS_I(inode));
1778         if (!delayed_node)
1779                 return -ENOENT;
1780
1781         mutex_lock(&delayed_node->mutex);
1782         if (!test_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags)) {
1783                 mutex_unlock(&delayed_node->mutex);
1784                 btrfs_release_delayed_node(delayed_node);
1785                 return -ENOENT;
1786         }
1787
1788         inode_item = &delayed_node->inode_item;
1789
1790         i_uid_write(inode, btrfs_stack_inode_uid(inode_item));
1791         i_gid_write(inode, btrfs_stack_inode_gid(inode_item));
1792         btrfs_i_size_write(inode, btrfs_stack_inode_size(inode_item));
1793         inode->i_mode = btrfs_stack_inode_mode(inode_item);
1794         set_nlink(inode, btrfs_stack_inode_nlink(inode_item));
1795         inode_set_bytes(inode, btrfs_stack_inode_nbytes(inode_item));
1796         BTRFS_I(inode)->generation = btrfs_stack_inode_generation(inode_item);
1797         BTRFS_I(inode)->last_trans = btrfs_stack_inode_transid(inode_item);
1798
1799         inode->i_version = btrfs_stack_inode_sequence(inode_item);
1800         inode->i_rdev = 0;
1801         *rdev = btrfs_stack_inode_rdev(inode_item);
1802         BTRFS_I(inode)->flags = btrfs_stack_inode_flags(inode_item);
1803
1804         inode->i_atime.tv_sec = btrfs_stack_timespec_sec(&inode_item->atime);
1805         inode->i_atime.tv_nsec = btrfs_stack_timespec_nsec(&inode_item->atime);
1806
1807         inode->i_mtime.tv_sec = btrfs_stack_timespec_sec(&inode_item->mtime);
1808         inode->i_mtime.tv_nsec = btrfs_stack_timespec_nsec(&inode_item->mtime);
1809
1810         inode->i_ctime.tv_sec = btrfs_stack_timespec_sec(&inode_item->ctime);
1811         inode->i_ctime.tv_nsec = btrfs_stack_timespec_nsec(&inode_item->ctime);
1812
1813         BTRFS_I(inode)->i_otime.tv_sec =
1814                 btrfs_stack_timespec_sec(&inode_item->otime);
1815         BTRFS_I(inode)->i_otime.tv_nsec =
1816                 btrfs_stack_timespec_nsec(&inode_item->otime);
1817
1818         inode->i_generation = BTRFS_I(inode)->generation;
1819         BTRFS_I(inode)->index_cnt = (u64)-1;
1820
1821         mutex_unlock(&delayed_node->mutex);
1822         btrfs_release_delayed_node(delayed_node);
1823         return 0;
1824 }
1825
1826 int btrfs_delayed_update_inode(struct btrfs_trans_handle *trans,
1827                                struct btrfs_root *root, struct inode *inode)
1828 {
1829         struct btrfs_delayed_node *delayed_node;
1830         int ret = 0;
1831
1832         delayed_node = btrfs_get_or_create_delayed_node(BTRFS_I(inode));
1833         if (IS_ERR(delayed_node))
1834                 return PTR_ERR(delayed_node);
1835
1836         mutex_lock(&delayed_node->mutex);
1837         if (test_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags)) {
1838                 fill_stack_inode_item(trans, &delayed_node->inode_item, inode);
1839                 goto release_node;
1840         }
1841
1842         ret = btrfs_delayed_inode_reserve_metadata(trans, root, BTRFS_I(inode),
1843                                                    delayed_node);
1844         if (ret)
1845                 goto release_node;
1846
1847         fill_stack_inode_item(trans, &delayed_node->inode_item, inode);
1848         set_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags);
1849         delayed_node->count++;
1850         atomic_inc(&root->fs_info->delayed_root->items);
1851 release_node:
1852         mutex_unlock(&delayed_node->mutex);
1853         btrfs_release_delayed_node(delayed_node);
1854         return ret;
1855 }
1856
1857 int btrfs_delayed_delete_inode_ref(struct btrfs_inode *inode)
1858 {
1859         struct btrfs_fs_info *fs_info = btrfs_sb(inode->vfs_inode.i_sb);
1860         struct btrfs_delayed_node *delayed_node;
1861
1862         /*
1863          * we don't do delayed inode updates during log recovery because it
1864          * leads to enospc problems.  This means we also can't do
1865          * delayed inode refs
1866          */
1867         if (test_bit(BTRFS_FS_LOG_RECOVERING, &fs_info->flags))
1868                 return -EAGAIN;
1869
1870         delayed_node = btrfs_get_or_create_delayed_node(inode);
1871         if (IS_ERR(delayed_node))
1872                 return PTR_ERR(delayed_node);
1873
1874         /*
1875          * We don't reserve space for inode ref deletion is because:
1876          * - We ONLY do async inode ref deletion for the inode who has only
1877          *   one link(i_nlink == 1), it means there is only one inode ref.
1878          *   And in most case, the inode ref and the inode item are in the
1879          *   same leaf, and we will deal with them at the same time.
1880          *   Since we are sure we will reserve the space for the inode item,
1881          *   it is unnecessary to reserve space for inode ref deletion.
1882          * - If the inode ref and the inode item are not in the same leaf,
1883          *   We also needn't worry about enospc problem, because we reserve
1884          *   much more space for the inode update than it needs.
1885          * - At the worst, we can steal some space from the global reservation.
1886          *   It is very rare.
1887          */
1888         mutex_lock(&delayed_node->mutex);
1889         if (test_bit(BTRFS_DELAYED_NODE_DEL_IREF, &delayed_node->flags))
1890                 goto release_node;
1891
1892         set_bit(BTRFS_DELAYED_NODE_DEL_IREF, &delayed_node->flags);
1893         delayed_node->count++;
1894         atomic_inc(&fs_info->delayed_root->items);
1895 release_node:
1896         mutex_unlock(&delayed_node->mutex);
1897         btrfs_release_delayed_node(delayed_node);
1898         return 0;
1899 }
1900
1901 static void __btrfs_kill_delayed_node(struct btrfs_delayed_node *delayed_node)
1902 {
1903         struct btrfs_root *root = delayed_node->root;
1904         struct btrfs_fs_info *fs_info = root->fs_info;
1905         struct btrfs_delayed_item *curr_item, *prev_item;
1906
1907         mutex_lock(&delayed_node->mutex);
1908         curr_item = __btrfs_first_delayed_insertion_item(delayed_node);
1909         while (curr_item) {
1910                 btrfs_delayed_item_release_metadata(fs_info, curr_item);
1911                 prev_item = curr_item;
1912                 curr_item = __btrfs_next_delayed_item(prev_item);
1913                 btrfs_release_delayed_item(prev_item);
1914         }
1915
1916         curr_item = __btrfs_first_delayed_deletion_item(delayed_node);
1917         while (curr_item) {
1918                 btrfs_delayed_item_release_metadata(fs_info, curr_item);
1919                 prev_item = curr_item;
1920                 curr_item = __btrfs_next_delayed_item(prev_item);
1921                 btrfs_release_delayed_item(prev_item);
1922         }
1923
1924         if (test_bit(BTRFS_DELAYED_NODE_DEL_IREF, &delayed_node->flags))
1925                 btrfs_release_delayed_iref(delayed_node);
1926
1927         if (test_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags)) {
1928                 btrfs_delayed_inode_release_metadata(fs_info, delayed_node);
1929                 btrfs_release_delayed_inode(delayed_node);
1930         }
1931         mutex_unlock(&delayed_node->mutex);
1932 }
1933
1934 void btrfs_kill_delayed_inode_items(struct inode *inode)
1935 {
1936         struct btrfs_delayed_node *delayed_node;
1937
1938         delayed_node = btrfs_get_delayed_node(BTRFS_I(inode));
1939         if (!delayed_node)
1940                 return;
1941
1942         __btrfs_kill_delayed_node(delayed_node);
1943         btrfs_release_delayed_node(delayed_node);
1944 }
1945
1946 void btrfs_kill_all_delayed_nodes(struct btrfs_root *root)
1947 {
1948         u64 inode_id = 0;
1949         struct btrfs_delayed_node *delayed_nodes[8];
1950         int i, n;
1951
1952         while (1) {
1953                 spin_lock(&root->inode_lock);
1954                 n = radix_tree_gang_lookup(&root->delayed_nodes_tree,
1955                                            (void **)delayed_nodes, inode_id,
1956                                            ARRAY_SIZE(delayed_nodes));
1957                 if (!n) {
1958                         spin_unlock(&root->inode_lock);
1959                         break;
1960                 }
1961
1962                 inode_id = delayed_nodes[n - 1]->inode_id + 1;
1963
1964                 for (i = 0; i < n; i++)
1965                         atomic_inc(&delayed_nodes[i]->refs);
1966                 spin_unlock(&root->inode_lock);
1967
1968                 for (i = 0; i < n; i++) {
1969                         __btrfs_kill_delayed_node(delayed_nodes[i]);
1970                         btrfs_release_delayed_node(delayed_nodes[i]);
1971                 }
1972         }
1973 }
1974
1975 void btrfs_destroy_delayed_inodes(struct btrfs_fs_info *fs_info)
1976 {
1977         struct btrfs_delayed_node *curr_node, *prev_node;
1978
1979         curr_node = btrfs_first_delayed_node(fs_info->delayed_root);
1980         while (curr_node) {
1981                 __btrfs_kill_delayed_node(curr_node);
1982
1983                 prev_node = curr_node;
1984                 curr_node = btrfs_next_delayed_node(curr_node);
1985                 btrfs_release_delayed_node(prev_node);
1986         }
1987 }
1988